While some floating debris, including the tail fin, was retrieved, the main wreckage from the jet - including the crucial flight recorders - could not be located.

Over the following months three extensive attempts to locate the wreckage were launched, each lasting several weeks, but without success.

But the Bureau d'Enquetes et d'Analyses says that a new search, which began last month, has turned up evidence of identifiable aircraft wreckage.

"We can say the accident site has been found," says a spokeswoman for the BEA, adding that further details will be released today.

"It's fantastic. It has been a big challenge."

AF447 was lost in extremely deep ocean water where the floor terrain is particularly harsh. The latest search effort has concentrated on sweeping a broad area within a circle some 40nm around the A330's last known position.

The BEA has not indicated precisely the location of the wreck relative to this position but states that the exploration team has been able to identify parts from data relayed by autonomous underwater vehicles.

Air France, which has co-funded the search effort with Airbus, confirms that the BEA has located the wreckage.

"This discovery, coming only days after the fourth sea search was launched, is good news indeed since it gives hope that information on the causes of the accident, so far unresolved, will be found," says Air France chief Pierre-Henri Gourgeon.

"I would like to thank not only the French authorities who employed hitherto unheard of means to pursue searches but also the crew of the [search vessel] Alucia and all the teams who are going to take part in, as we all hope, the retrieval of the flight recorders."

No immediate information is available on the next stage of the operation but the BEA previously said that, if a search was successful, a separate recovery phase would be initiated to retrieve the wreckage.